alt Hacker NewsI haven't tried actual mayo, but I did once try Miracle Whip (which is my preferred condiment in place of mayo). I would strongly advise avoiding that - the grilled cheese made with Miracle Whip was truly nasty. Proper mayo must be different in a way that makes it more effective in this task.
Real mayo is an emulsion of eggs and oil.
Miracle Whip? What's the sugar content on that label and the other ingredients. Is this even sold as food like thing or is it more of a candy condiment like 'chocolate sauce'?